Abstract

Microlithography is used to transfer a geometrical pattern from a mask to a substrate. The principle of the process is similar to any imaging method. A source emits radiation which may consist of photons, electrons, or ions. An object represented by a layout on a mask will be imaged by an optical system to a receptor called a photoresist. The radiation will change the chemical bindings of the resist. The pattern generated in the photoresist is then transferred to the underlying substrate which in the case of semiconductor manufacturing is usually a wafer of silicon. The resolution limit for lithography is determined by the optical system, the photochemistry of the resist, and the transfer process to the substrate. This paper will cover only the optical part of this topic.

© 1984 Optical Society of America